فهرست مطالب nima amani

Building insulation stands out as one of the most widely employed strategies to enhance energy efficiency in the building sector. Increasing the thickness of thermal insulation is a conventional approach to meet the design requirements of these structures. In this study, a novel approach to augment the thermal resistance of external building walls is explored by simultaneously employing multiple thermal insulation materials, comparing this with a single-layer insulation setup. Three typical insulation materials with varying thicknesses are utilized to create a three-layer insulation system, which is applied to a case study involving a house-like cubicle situated in the 3B climate zone per ASHRAE 169-2006. The findings indicate that merely increasing the thickness of a single-layer insulation does not invariably yield optimal solutions. A comparison of two non-dominated solutions, both with a thickness of 15 cm, reveals that both alternatives achieve approximately 70 percent energy savings compared to the base model lacking wall insulation. Furthermore, the environmental impact of the three-layer solution is 45%, and its cost is 43% lower than that of the single-layer solution. In summary, multi-layer thermal insulation emerges as an effective and environmentally friendly method. The results emphasize that the consideration of multi-layer insulation systems can establish a continuous decision-making space, enabling the identification of at least one insulation scenario aligned with design requirements. To facilitate designers in the initial stages of thermal insulation design, a rapid and simplified design model has been developed based on the results. The methodology proposed in this study is generalizable and can be applied to all climate zones, offering a comprehensive design tool without the need for intricate calculations.

In One of the most important issues of project-oriented employers and senior managers is evaluating the performance of the organization's projects as well as ranking the projects based on applied indicators during project implementation. The lack of a system of method in a system means not knowing the contractors' work defects during execution, which in itself causes time, quality and economic losses. The purpose of this study is to identify and compare current operational strategies to standardize contractors' decisions in construction projects. In this research a questionnaire is designed by studying and reviewing scientific articles from databases and interviewing executives of companies that formulate and execute contractors' operational strategies. Then, the questionnaire is distributed among the executives of the contractor firms and they score the factors according to the two hypotheses. The answer will be weighted and analyzed using statistical software. The published factors are then prioritized around operational strategies. The results show that the strategy of managing the additional work done in the project is in the first place and in the next rankings respectively of the other strategies including contractor performance, resource management and stakeholder management.Also, all the factors that were designed in the questionnaire are the published characteristics regarding the common operational strategies in terms of decision categorization. In the analysis, the factors have an acceptable value and none of them can be ruled out.

Rubber dam in construction projects is a relatively new technology, whose history of usage goes back to about 60 years ago. Considering the short period of presence of this technology in Iran, there is not enough knowledge of its dimensions, These projects have a different contract. whether in the section of contract preparation and arrangement or in the execution section. Therefore, majority of the current projects are affected by numerous disputes between the contractor, the consultant and the employer and these projects are accompanied by delay in completion time and increase in construction costs. In this study, first, the effective factors in claiming were identified and then prioritized by preparing and distributing questionnaires and collecting the opinions of experts, who work in rubber dam projects. In the next step by referring to the existing laws and regulations, private terms of current contracts as well as the results of numerous meetings of claim management which were held in various projects, a proper strategy was proposed based on the suggested priority. This strategy was finally modified and presented after confirmation of five experts. Finally, it was concluded that the approaches that led to the prevention with 80.62 percentages were more favorable than the agreement strategies with19.38 percentages.

One of the main reasons of environmental pollution is energy consumption in buildings. Today, the use of renewable energy sources is increasing dramatically. Among these sources, solar energy has favorable costs for various applications. This study examined a commercial building in a hot and humid climate. The findings showed that choosing the optimal angle of solar panels with the goal of optimized energy consumption would yield reduced costs and less environmental pollutants with the least cost and maximum energy absorption. In this study, to calculate the energy requirements of the building, DesignBuilder software was used. To study the solar angles and estimate the energy produced by the solar panels, Polysun software was used after simulating the building energy. Energy simulation results showed that the whole building energy consumption was 26604 kWh/year. Finally, the evaluation results of solar panels showed that the energy produced by photovoltaic modules at an optimal angle of 31° would be equal to 26978 kWh/year, which is more than the energy required by the building. This system can prevent 14471 kg of carbon dioxide emissions annually. Sustainable energy criteria showed that for the studied building, photovoltaic modules could be used in energy production to reach a zero-energy system connected to the grid with an annual energy balance.

Traditionally, building energy model is created in isolation from the architectural building information model and energy analyses have relied on a single analysis tool. The building energy model can be generated more quickly by leveraging existing data from the BIM. The impacts of energy consumption are significant in the building usage phase, which can last several decades. Due to the large share of the final energy consumption in the building sector, accurate analysis of thermal and cooling loads of a building and the efforts to reduce energy losses represent an effective way to reduce energy consumption. Therefore, it is essential to analyze the building energy performance in the design phase, which is when critical decisions are made. This study aims to investigate the impact of the building components and construction materials on building energy efficiency using Building Information Modeling (BIM) technology in a mild climate zone. After reviewing the proposed designs, the main building form was chosen for energy modeling and analysis. Then, building energy consumption analysis was performed based on the basic parameters of the building energy model. Eventually, the most optimal mode was selected by examining different energy consumption forms. This study showed that the building HVAC system always had the largest share of energy consumption. Finally, the results of parametric studies on alternative schemes of energy use intensity optimization showed that 22.59 % savings could be achieved as compared to the base building model in a 30-year time horizon

The objective of this study is to evaluate the energy efficiency of residential buildings by using natural energy and optimizing the choice of materials for heat and cold saving with the Ecotect simulation software. According to analysis and simulation was found that the optimum material of main building components in a mild climate zone of Rasht city is the Brick Conc block Plaster for wall with total radiation incident of 340 W/m2 and radiation absorption of 240 W/m2; Double Glazed-Low E for window with total radiation incident 340 W/m2 and radiation absorption of 100 W/m2; Foam Core Ply Wood for door with total radiation incident of 340 W/m2 and radiation absorption of 200 W/m2; ConcSlab- OnGround for floor with total radiation incident of 340 W/m2 and radiation absorption of 220 W/m2; and Conc Roof Asphalt for roof with total radiation incident of 340 W/m2 and radiation absorption of 300 W/m2. According to the hourly temperature analysis for all storeys of the building in the two hot and cold days of the year, it is determined by the design and material selection requirements that the building will be in the near thermal comfort zone (below 30 degrees) in the warm season.

The objective of this study is to evaluate and design a zero energy building in cold and dry climates. In this study, energy consumption will be reduced by using of the solar-powered systems and techniques for the use of maximum energy from renewable sources.

A residential building is evaluated as a case study. This building includes one floor with an area of 100 square meters with 4 people in cold and dry climate of Mashhad in the north east of Iran. For thermal simulation, weather information (temperature, air, sunshine, wind, rain, and sunlight) is obtained from the weather station and climate database and the Meteonorm software. Design Builder software is used to simulate and analyze the dynamic heat of the structure.

The results of this simulation show that 30% of the annual energy consumption of the building, taking into account the principles of inactive design (optimal selection, wall truss, shade, appropriate fitting) will be reduced from 2544.3 KWh to 1776 KWh. Subsequently, with the annual energy requirement, PVSyst software is designed to design a photovoltaic solar system with an annual energy of 2629.1 KWh.

The comparative comparison of equation values by applying a 1.4 coefficient of confidence indicates that construction of zero-energy building is possible in a cold and dry climate and is created to achieve sustainable and environmentally sustainable.

Risk management (RM) should be implemented in construction projects to assure the achievement of project objectives, regardless of project size and dimensions. This study aims to investigate RM in small projects in Iran in terms of status, barriers and impact on project performance. To achieve the objectives, a questionnaire survey was conducted and data was collected from 40 projects submitted by 25 experts from 5 companies. The analysis results indicated a relatively low level of RM implementation in the small construction projects, and “shortage of potential benefits”, “not being economical”, “shortage of time” and “shortage of budget” were prominent barriers. Also, the results reported a positive correlation between RM implementation and improvement in quality, cost and schedule performance of small construction projects. Findings of this study can provide an in-depth understanding of RM in small projects in Iran and make benefits of RM implementation convincing to stakeholders of small projects.